Rome and Parthia at War

The wars between Rome and the Parthian Empire, which took place roughly from 53 BC to 217 AD, were a unique episode in classical history. Although Rome conquered nearly the entire civilized world around the Mediterranean, Rome could never conquer Parthia. When Roman expansion reached Mesopotamia, the Parthian Empire had already been prospering as a major power whose outskirts reached far into the east and trade routes ran deep into China. When Roman and Parthian borders finally met, the centuries that followed were a time of diplomacy and war between two empires of distinct cultures and methods of war.

Roman-Parthian relations dominated international policy in the classical near east. As opposed to less organized tribes on Rome’s European borders, the Parthians were a sophisticated culture of commerce and empire. The Parthians garnered significant wealth from its trade routes and its cities stood as some of the largest in the world. The entire diplomatic history between the two states is too complex. For that reason, we will focus on the stories of four Roman characters, three of whom ventured into Parthian lands. Regrettably, due to the scarcity of Parthian sources, the narrative will be told mainly from the Roman perspective.

Around 250 B.C.E. the Parthians revolted against their Seleucid overlords who ruled the Iranian region as successors of Alexander. The Parthians were an Iranian nomadic group whose homelands were located in central Asia, near Bactria. By 139 B.C.E. the Parthians had conquered nearly all of the Seleucid Empire, including its significant cities in Mesopotamia. By 53 B.C.E. the Parthian Empire of the Arsacid Dynasty stretched from eastern Anatolia to the Indus River, a territory at least as large as the Roman Republic at the time. The Roman Republic, interestingly, had also been expanding at roughly the same timeframe. In the third century BCE, Rome successfully fought for control of Mediterranean against its Carthaginian and Macedonian neighbors. By 146, Rome had destroyed Carthage and crushed the Macedonian power in Greece. Like how Parthian expansion crushed Seleucid power from the east, Roman expansion finished off the remaining western fragments of the Seleucid Empire in 65 BCE. Therefore, Rome and Parthia were two rising powers in the ancient world. It is at this timeframe that our stories begin.

The Parthian Empire

Roman military operations in the east first made diplomatic contact with the Parthians in 96 BCE. Although the Roman general Sulla did not treat the Parthian envoy with respect, a treaty that definited the border as the Euphrates River was ratified by both parties.1While the Parthians were unimpressed by Sulla’s personality, their policy toward the Romans for the next thirty years was mainly peaceful. The Parthians needed to secure their western borders, as their empire was still expanding toward the east. Likewise, the Romans were also in a period of expansion and had plenty of affairs of their own.

As the Romans became more established as a power, peace came slowly to an end. In 64, a Roman governor of Syria named Galbinus got involved in a power-struggle over the Parthia throne. In support of a claimant, Galbinus briefly entered Parthian land with his army. He withdrew quickly, but later made the proposal for a large-scale invasion, which was outright rejected by the Senate. However, the Roman senate itself was slowly losing control to three powerful men who came to dominate Roman politics: Caesar, Pompey and Crassus – together known as the First Triumvirate. It was Crassus who would ultimately bring war.

The Roman Republic

II. Marcus Licinius Crassus

Crassus was a man who worked his way up to the top through “conventional” means of politics. His service to Sulla’s campaign gave his career a good start, after which, he amassed his wealth through skillful property ownership and made his way through politics. The outcome of his rise to prominence was his new reputation as the richest man in Rome and his position of Consul in 70 BC. It was around that time that the political pact known as First Triumvirate was formed among Crassus the richest in Rome, Pompey the greatest general of the republic, and the young but promising Julius Caesar. However, powerful alliances entail great dangers. Crassus had always been wary of Pompey’s power in the republic. He understood that Pompey’s fame in generalship was enormous and something that he lacked. Crassus knew that his place in the Triumvirate was owed solely to his wealth. With Caesar’s successful campaign in Gaul, Crassus knew that wealth alone was not enough. He needed glory. To Crassus, Parthia offered that opportunity for gloria.

Crassus went forth with his plan and obtained the province of Syria. While people in Rome knew that Crassus was about to attack, a statement of war was never issued by the Senate, thus making Crassus’ invasion entirely a “private” war. In 54 BC, Crassus began his campaign with the taking of several cities in Mesopotamia. The Parthians did not immediately respond, possibly because their King Orestes had only recently been enthroned after a power struggle, and thus did not want to rush the formation of an army from the nobility. Eventually, after several skirmishes, a Parthian army under the general Surena of about 9,000 horse archers and 1000 heavy cavalry (Cataphracts) approached the city of Carrhae. Crassus marched toward his enemy with a much larger force of about 40,000 infantry and 3000 cavalry. As the armies met, the Parthian horse archers showed the Romans with arrows. Able to take no more, Crassus sent a detachment of his cavalry supported by archers and legionnaires under his son to charge the Parthians. This detachment was decisively destroyed by the superior cavalry of the Parthians, who then counterattacked carrying the severed head of Crassus’ son mounted on a spear. The Romans, although significantly outnumbering the Parthians, suffered heavy loses as they were shot down by the Parthian horse archers, whose arrows pierced Roman equipment at close range. Into night, the remaining Roman forces withdrew or fled from the battlefield into Carrhae. Crassus attempted to escape back to Syria, but was unable to find a way due to poor terrain intelligence. The Romans were intercepted and took refugee on a hill. There, the Parthian commander offered a truce to Crassus, stating that he did not wish for a full-blown war. However, negotiations failed, a fight erupted and Crassus was killed fighting his way out. In the end, only 10,000 Romans made it back. The rest were killed or captured by the Parthians.

According to one account, the Parthians King Orodes received Crassus’s corpse and poured molten gold into his mouth…if this was the case, it would have been an ironic end to a man’s hunt for greed.

The disaster at Carrhae was symbolic of the Roman Republic’s limitations in its expansion to the east. However, while Crassus’s story is probably the most well known in the Roman-Parthian wars, it is by no means the end. The invasion of Crassus dramatically altered the relations between the two states. Although the Parthians understood that Crassus acted on his own foolishness to wage war, they also understood the growing threat of the Romans. Two years after Carrhae, the Parthians under their Prince Pacorus invaded Syria. The Romans defended well but Pacorus returned in 40 BC with a larger force, this time with the rebel Roman Labienus at his service. Pacorus and Labienus defeated the Roman governor of Syria and overran the province. In addition, Pacorus placed his candidate, Antigonus, on the throne of the Jews. The news arrived at Rome in great embarrassment. The Roman general Ventidius was to lead the Roman forces in the upcoming battles.

III. Publius Ventidius Brussus

Ventidius lies among the accomplished but forgotten generals in history. Ventidius had humble beginnings. Since his parents was disgraced and taken prisoner in the “Social War,” Ventidius joined the Legions as his best choice. Ventidius proved to be a capable and distinguished commander under Caesar, whose influence accelerated Venditius’ career. After Caesar’s murder, Venditius served under Antony, who sent him to deal with the Parthian invasion.

Ventidius took a force of 11 legions, including a large number of slingers to defend against horse archery, for the Romans had learned that unsupported heavy infantry in the open were highly vulnerable. Ventidius immediately attacked Labienus’ army, which withdrew to his Parthian ally. Labienus regrouped with Pacorus and the armies met somewhere at the Taurus Mountains. Unlike Crassus who ventured into open territory, the hilly terrain of the Taurus negated the Parthian strength in cavalry. Ventidius positioned his men on a hill with his infantry in a defensive with his slingers while the Parthian cavalry poised themselves at the foot of the hill ready to attack. Eager for battle, the Parthian army consisting of a large number of nobles in cataphract armor, attacked upward while all of a sudden, Ventidius’ men charged downward. Unable to beat back the Roman infantry in an uphill battle, the Parthians were routed. Pacorus withdrew but Labienus was killed in the battle. Labienus’ rebels joined Ventidius’ men.

The Parthians withdrew to Amanus Pass where they met Ventidius’ army for another battle. Pacorus was defeated again when his Cataphracts were lured into an ambush. Pacorus withdrew his army from Syria, which was promptly retaken by the Romans. However, Pacorus returned in 38 BCE for another invasion. While Syria was under Roman control, the region had become unstable due to the recent war. Ventidius needed a decisive victory. He conceived an excellent plan using counter-spying. He knew that the Parthians had agents that were gathering intelligence from his army, among them, Prince Pharnaeus of Cyrrhestica. With this in mind, Ventidius fed false information to the Parthian spies, who delayed and steered Pacorus’ army into hilly terrain.

A battle was fought in the hilly grounds of Cyrrhestica. Like their first encounter, Ventidius held his position on a hill. In an attempt to erase the first defeat, Pacorus once again led his cavalry in an uphill attack, supported by horse archers. Once again, Ventidius charged his men downhill. The Parthians fell back. Their heavy cavalry stood ground at the foot of the hill and a fierce clash ensued, but their Prince Pacorus was killed in the fighting. As soon as he fell, a number of the Parthian warriors turned from battle and fled, earning Ventidius another victory.

According to Plutarch, the Roman victory “fully avenged Carrhae.” With the Parthians driven out, stability was restored to the region. In Judea, Antigonus was driven out and the Roman-backed King Herrod was installed as ruler. In Rome, Ventidius was hailed Imperator and given a celebration of triumph, which he shared with Marc Antony, since Ventidius had been fighting under Antony’s command. However, from then on, no more is known about the service of Ventidius.

IV. Antony, Augustus and the Roman Principate

Following the campaign of his subordinate, Marc Antony decided to take matters into his own hands. In 37, Antony set out with 70,000 men to begin his own Parthian war. He took a route through Armenia and arrived in Parthian territory besieging the Parthian stronghold of Phraaspa. After skirmishes on the outskirts of the city, the two armies met in battle. The detail of the battle, which appears to be inconclusive, is not exactly certain. But with the lack of progress, Antony was forced to conclude his campaign with by withdrawing his army back to Armenia. Returning to Armenia, Antony’s army was harassed by the Parthians and met with disease. Only half of Antony’s army returned home.

In 31 BC, Antony was defeated by Octavian at Actium, thus marking the end of the Roman Republic and the beginning of the Roman Empire. The new era in Roman history, known as the Pax Romana (Roman Peace), also changed the nature of the Roman-Parthian relation. For the most part, the early “Roman Peace” that came out of exhaustion from the Roman civil wars carried through to their Parthian relations. The earlier defeats of Crassus and Antony still presented a dilemma. But Augustus did not want war with Parthia, even when presented the chance. Instead, by negotiation, Augustus was able to have the Eagle Standards lost by Crassus returned to the Romans. For the most part, relations between the two states took the form of “diplomatic maneuvering” rather than open war. Notable among the events is an Italian slave girl named Musa, who was sent by Augustus to the Parthian King. Some of Musa’s sons moved their residences into Roman realms, where they became a group of exiled Parthian nobility that the Romans would later support as claimants to thrones. The situation is complicated by turmoil in Parthia, where the country was stuck by rapid succession of kings. The Romans were very much involved with the chaos in Parthia, where they attempted several times to support various claimants to the Parthian throne. However, the details are far to complex to pursue here.

Roman-Parthian became increasingly centered on Armenia, which was located in the middle between Parthian and the Roman Empire. The Armenians had already played a role in the early history of the Roman-Parthian relations. In both Crassus’ and Antony’s campaigns, the Armenian king had a large role as a guide, and “betrayer,” as some sources state. Throughout the remaining history of the relations, Armenia would the role of a “buffer state” between the two powers. An advance on Armenia from one side was often interpreted as pretext to war.

The political turmoil the Parthian Empire, as aforementioned, was also a significant factor attributing to the lack of open war during the early Pax Romana period. The Parthians had a number of problems on their other borders. In 20 CE, Parthian generals who conquered the regions of northern India declared independence to form the “Indo-Parthian Kingdom.” In 75 CE, Sarmatian tribes overran Parthia’s northern borders, deposing local Parthian nobles. Internal havoc continued to take its toll. It is therefore accurate to describe Parthia as a state in decline. Although the Romans themselves had also overextended and faced problems of their own, the declining stability in Parthia left it vulnerable. When Trajan became Emperor in Rome, Parthia was to face a very dangerous threat of the skillful military emperor.

V. Trajan and his Successors

Trajan holds his position in history as one of the greatest emperors of Rome. It is said that the Romans wished their future emperors to be “luckier than Augustus and better than Trajan,” taking these two emperors as models for future rulers. Trajan was born in a family from Spain, and as such became the first emperor of non-Italian descent. He owed much all to his successful relation to the emperor Nerva, who took Trajan as adopted son. When Trajan became Emperor, he embarked on a series of campaigns to expand the realms of the empire. Against Parthia, Trajan’s justification for war was that in 110 AD, the Parthian King removed the Roman-appointed king of Armenia and installed Axidares, his own nominee, the throne. Trajan argued that this act was a violation of treaty.

In 113 AD, Trajan sailed from Rome to begin his campaign against Parthia. He first stopped in Athens where Parthian envoys greeted him with olive branches, a signal for peace. In addition, the Parthian King decided to retract his nomination by deposing Axidares and was prepared to negotiate regarding the state of Armenia. Trajan ignored these offers for peace and continued with his plans. In addition, Trajan declared that Armenia was to become a Roman province. On his way to Parthia, Trajan conquered Armenia and consolidated it as a province.

Trajan then proceeded into Mesopotamia with eleven Legions, taking the city of Nisibis and Batnae in September 115 AD. For these early victories, he was granted the title Parthicus by the Senate, which he was hesitant to accept. Continuing his march, Trajan crossed the Tigris River using boats and reached the city of Babylon, before returning to Antioch to pass the winter. In the following year, Trajan returned to Mesopotamia to continue his conquest. He crossed the Tigris, reaffirmed his conquest of Adiabene and proceeded to Ctesiphon, the most important capital of the Parthian Empire. The Parthian King fled and the city fell without much of a siege. At that point, Trajan formally incorporated the title Parthicus into his name to his victory, along with the phrase Parthia Capta (Parthia seized) on his coins. During all of this campaign, he had been largely unopposed on the field by the Parthians, who had been severely weakened in a civil war that was still ongoing during Trajan’s campaign. No major pitched battles were recorded and it appears that most of the campaign had consisted of sieges. Trajan himself was disappointed, for he had not won a great victory on the field against the “King of Kings”, as Alexander the Great had centuries before him. Upon reaching the Persian Gulf, it is said that that he lamented as he saw a ship leaving for India, where he could not bring his conquest to.

In southern Mesopotamia, Trajan learned that the cities he conquered in the north were revolting. He then dispatched his generals who recaptured the region. Nisibis was recaptured and Edessa was sacked. Then, Trajan received word that a Parthian general Parthamastaphes, nephew of the King, was arriving with an army. Interestingly, no battle was fought. Instead, Trajan placed Parthamastaphes on the throne of Ctesiphon as puppet Trajan’s puppet king. However, Trajan’s campaign turned for the worse. Armenia revolted from Roman rule and Trajan was forced to concede much of his Armenian conquests. In Mesopotamia, the city of Hatra resisted Trajan’s siege. Unable to take the city and short of supplies and campaign resources, Trajan’s campaign came to a close. The emperor withdrew his men from southern Mesopotamia to consolidate his gains in the north. Trajan planned to embark on another campaign, but was struck by illness. Trajan died in 117 AD, after returning home.

Trajan’s campaign displayed eagerness for glory of the Roman emperors. With his conquests, Trajan’s rule represented the pinnacle of Rome’s expansion. Yet the ultimate failure of the campaign in Mesopotamia reflected the limited potential for further Roman expansion. On the other hand, the quick capture of the Parthian capital and its ongoing civil war reflects the decaying nature of the Parthian state. Trajan’s successor, Hadrian, decided that the Empire could not sustain its eastern conquests. He withdrew the garrisons from Mesopotamia. The border between the two empires fell back to the Euphrates.

In 161, quarrels over Armenia escalated into another Roman-Parthian war. Parthia had recently recovered from a civil war that ended with Volgases’s victory over his rival Oseroes in 129. However, the Parthian King, Volgases IV, had greater ambitions. When the Roman Emperor Antinius Pius died in 161, Volgases attacked and made Armenia a dependency. Volgases then continued to attack Roman Syria, defeating a local army there. Unfortunately, the Romans retaliated two years later. Sent by the emperor Verus, The Roman general Priscus defeated the Parthian garrison in Armenia and installed a Roman-appointed king to the Armenian throne. A year later, Avidius Cassius campaigned into Mesopotamia. Once again, Ctesiphon and other important cities such as Nisibis and Seleucia fell to the Romans. However, Cassius’ army was struck by plague and was forced to withdraw. Most of the territories were eventually returned to the Parthians after peace was made.

The second Roman conquest of Mesopotamia, although brief, confirmed the reversal of the centuries of cease fire that marked the first century. Although neither side could permanently gain much land, the second capture of Ctesiphon signified the withering away of the Parthian state. Its hold on Mesopotamia had been seriously undermined by repeated Roman conquest of the cities of the region.

VI. Septimius Severus

Our story now comes to the life and times of the Emperor Septimius Severus. As with Trajan, Septimius did not hail from a family of Italian Roman origin. Instead, his family was based in North Africa, of possible Berber or Punic descent. As with Trajan, Septimius was an emperor with a very keen grasp of military affairs. In 191, Septimius was assigned general of the Legions of Pannonia, southwest of modern Hungary. When the Emperor Pertinax was assassinated in 193, Septimius seized his chance. He had his troops declare him Emperor. However, two other generals made bids to become emperor, including Pescennius Niger of Syria. Amist this chaos, the Parthian King Volgases V made his gamble in supporting Niger as Emperor of Rome.

It was a bad decision with far reaching consequences. In the same year, Niger was defeated by Septimius in three consecutive battles fought in Asia Minor. At Issus, the defeated Niger was killed while fleeing to Parthia. Septimius then brought his attention to the Parthians, whom he believed to be his enemy for supporting his rival Niger. Following his victory over Niger, Septimius invaded Northern Mesopotamia, which then were ruled by vassal states of Parthia. The region, including the crucial of Nisibis, was conquered and Septimius was granted the title Parthicus by the Senate. He did not accept the title, since he had only defeated Parthian vassals. Furthermore, Septimius did not yet want to offend the Parthians too much, as his rule in Western Europe had not yet been consolidated.

Captured Parthian. Relief on the Arch of Septimius Severus, on which Septimius' victories against Parthia are commenorated.

In 197, Septimius defeated his last remaining rivals to the Roman throne. He then turned his attention to Parthia once again. It could have very well been the case that his Expdito Parthica (Parthian Expedition) was drawn more by the thirst for glory than by any practical necessity. However, the Parthians had begun retaliating and action was needed. In 197, Septimius returned to Mesoptamia, where he captured the important cities of Seleucia, Babylon, both of which were abandoned by the Parthians garrisons. Finally, he entered Ctesiphon in the winter of that year. The capture of Ctesiphon was particularly devastating. Septimius gave his soldiers the liberty to plunder the city and brutal slaughter ensued. According to Cassius Dio, as many as 100,000 women and children were sold into slavery. An enormous amount of treasure was carried off from the city.

Like his predecessors, Septimius did not garrison Ctesiphon. When the plundering was complete, Septimius withdrew from Ctesiphon and southern Mesopotamia. He then turned to the city of Hatra, the same city that Trajan could not conquer. As had been in the past, Hatra successfully resisted. Septimius returned to assault the city the following year, but only to lose a number of his men and siege equipment. Septimius retired from campaigning and returned to consolidate his conquests in Northern Mesopotamia.

VII. The final stages of the wars and the rise of the Sassanids

While Septimius could not claim total victory in Mesopotamia, his conquest of Ctesiphon marked the near end of the Parthian Empire. Nonetheless, the usual affairs of conflict continued. The last conflict between Rome and Parthia occurred at around 217, when a series of political complications escalated into war. The emperor Caracalla, son of Septimius Severus, entered Mesopotamia, but was assassinated on campaign. Macrinus succeeded Caracalla and renewed the campaign against Parthia. In the summer of 217 near the city of Nisibis, Macrinus was defeated by the Parthian army and was forced to make embarrassing concessions to the Parthians. That battle was the last in the Roman-Parthian wars.

In 224, the Parthian King was killed in battle by Ardashir, who revolted against his overlord. The Arsacid (Parthian) dynasty was no more. In 226, Ardashir entered Ctesiphon and established the Sassanid Dynasty with himself as the new “King of Kings.” All former Parthian territories became incorporated into the Sassanid Empire, a new power that came to rule Persia. Unlike their Parthian predecessors, the Sassanids were more centralized and more aggressive. To the west, the Sassanids waged war against their rivals, the Romans. But that’s another story.

VIII. Conclusion: Legacy of the Roman-Parthian Wars

Exactly what role did the wars between Rome and Parthia play in history? From one perspective, the Roman-Parthian wars can be seen as part of a larger picture of contact between civilizations. In the political history of the classical near east, Rome and Parthia were the dominant players. Their wars against each other can be seen as critical points in the diplomatic relation in the region. The importance of the wars in political history can be further extended to cultural history. Since Parthia was essentially the gateway of land trade into the east, cultural contact between Rome and Parthia was nothing short of significant. Thus, in order to understand the cultural development of the classical near east, the Parthian wars must not be neglected. In certain occasion, warfare had a direct impact on cultural development. Constant Roman invasion of northern Mesopotamia resulted in an increased Romanization of cities such as Nisibis. On the other hand, Rome’s wars with Parthia had a profound military influence its military, particularly in the strengthening of cavalry in eastern Roman armies.

In Roman history, Parthia’s legacy is its role as the great rival of the east. Unlike Rome’s other rivals - the tribal societies in Europe, Parthia’s realm was vast, its culture was sophisticated, and its wealth was enormous. As a military rival, however, Parthia was at most an average threat to the Romans. There were few instances in which the Parthians were a serious threat to the Roman Empire; while on the other hand, the Romans were able to make significant conquests on Parthian lands. Compared to other powers in the east that came after the Parthians, namely the Palmyrenes and the Sassanids, the Parthians were far less aggressive and their campaigns against Rome far less destructive. Although the Parthians fielded impressive cavalry, they lacked the manpower that Rome could field. The feudal structure of the Parthian empire may have limited its ability to project large armies against Rome. However, despite suffering punitive expeditions by the Roman Empire, the Parthian victory at the Battle of Carrhae has remained a lasting memory in the history that symbolizes the limit of Roman power, even though significance of the battle has been exaggerated.

A note that should be made that the events presented here are as described by Roman accounts. Since there is a scarcity of Parthian sources, we are unable to cross reference the events presented by Roman accounts. As with all historical accounts, there is a degree of uncertainty and incompleteness that must be considered. It should also be noted that the term “Parthian” is a Roman name, and it is unlikely that the Parthians themselves used a similar term to refer to their state.

Some may argue that the Roman-Parthian wars were largely reflective of internal turmoil within the two states. This view does have some truth, in that both Rome and Parthia took advantage of the internal civil wars within their rivals. The success of later Roman conquerors in taking multiple key cities in Mesopotamia may have been attributed weakness within the Parthian government. It is also interesting to note that despite three captures of the Parthian capital by the Romans, it was the fourth capture, by an internal foe, that ultimately ended the empire. This fact reminds us that both Rome and Parthia had overextended and each had little power left to conquer each other. Yet, each empire spent a considerable amount of resources trying to invade or take advantage of the other. Thus, the Roman-Parthian wars offer us a view of the complex international politics in the ancient world.